Swimming pool pump and contactor.

[Lofty]

Hi All,

Got a call today about a DB tripping over the week-end.
Narrowed it down to the switches and contactor for their outdoor pool. Now here's the issue.

The contactor (Old MEM 3P adjustable 4-8A) switches both the pool pump and the oil fired boiler (on the same contacts) via an old style Sangamo timeclock. All of which has been working fine for the last 10-15 years.
If both loads are disconnected from the contactor the contactor holds, however connect EITHER the boiler OR the pump and it takes out the RCD. All IR measurements on the contactor seem to be OK, and when it trips there's no visual signs i.e. arcing from the coil to earth.
Could it be the contactor failing under load ?.

Cheers,
Lofty.

 

[Engineer54]

This sounds like a really old POOL panel. As it's been in service now for around 15 years, it really is time for it to be renewed. Is the RCD protection incorporated within the pool panel, ...it should be?? Sounds to me like the RCD device has seen better days and now has just given up!! ...lol!!

Newer style panels are completly self contained and generally Din rail based. Apart from the pools underwater lighting 12V 100/300W TXs that is...

 

[Knobhead]

Not the contactor as E54 says. Test the pump and boiler IR separately. But I'm going to worsen the odds by backing alongside E54 that the RCD is long past it’s retirement! Change it.

 

[Lofty]

Hi,
The RCD is on the DB in the main house. There's a seperate (Old Wylex ) DB in the pool house. Yes it is old, it's looks to havee been 'cobbled' together using FCU's and DP switch etc. This system was 'inherited' by the current owners of the house.
RCD is on a proteus board and of course when it trips it takes out 4 other circuits. Agreed it should really be independent but they are desperate to get the pump running as they also have an algae problem ( leaving that to the 'poolman') and various chemicals need to be pumped through it. As either load seems to trip it, I'm thinking that there may be an earth transient leak ??? or possibly the old bakelite is breaking down ???

Cheers,
Lofty.

 

[Lofty]

Hi Tony,
Thanks for the reply. Must've come in whilst I was typing.

Cheers,
Lofty.

 

[Engineer54]

Hi,
The RCD is on the DB in the main house. There's a seperate (Old Wylex ) DB in the pool house. Yes it is old, it's looks to havee been 'cobbled' together using FCU's and DP switch etc. This system was 'inherited' by the current owners of the house.
RCD is on a proteus board and of course when it trips it takes out 4 other circuits. Agreed it should really be independent but they are desperate to get the pump running as they also have an algae problem ( leaving that to the 'poolman') and various chemicals need to be pumped through it. As either load seems to trip it, I'm thinking that there may be an earth transient leak ??? or possibly the old bakelite is breaking down ???

Cheers,
Lofty.

Nothing to stop you lashing up a temporary supply for the main pool pump, It only needs to be for 24 hours. The pool man just needs to shock the pool with chlorine granules. and a bit of algaecide. In the meantime, get the clients to purchase an off the shelf pool panel. just need to tell the supplier what you want controlling the pool lamp wattage and what the pump motor rating is.

Normally the pool panel will consist of ...TXs for pool lamps, timer and protection for primary/secondary for same. Pool timer, pump motor starter/contactor, and protection, HOA door controls for pump and pool lighting, overall RCD device, main isolator. But they come in many other configurations, to suit standard type installations.

I take it it's a single phase set-up?? If so, nothing wrong in using the the boiler supply thru a spare contactor connection, on the motor starter/contactor. But far better to be controlled on it's own relay. There are going to be times you don't want the boiler coming on, though being the UK not that often i think!! ...lol!!! I would take the supply for this pool installation, from a non RCD protected way in the CU, or provide an S type device.